Studies are in progress on retinal metabolism employing freeze-dried sections of frog retina. The concentrations of adenyl nucleotides (ATP, ADP and AMP) and P-creatine are being measured as a function of dark adaptation or light exposure of either 2 sec or 2 min. Cyclic nucleotide concentrations will be measured, since cyclic GMP has been implicated in the transduction of the light response in rod-dominated retinas. A study is in progress of granular dystrophy in the cornea, an autosomal-linked hereditary disease. Preliminary evidence indicates that there are at least two abnormal proteins in the diseased cornea, and there is a high level of sulfur-containing material. Immunological studies have demonstrated that these proteins are not keratin (which they resemble electrophoretically) but may be related to elastin.